angular directive output

JavaScript
@Component({...})
export class CounterComponent {

  @Input()
  count: number = 0;

  @Output()
  change: EventEmitter<number> = new EventEmitter<number>();

  increment() {
    this.count++;
    this.change.emit(this.count);
  }

  decrement() {
    this.count--;
    this.change.emit(this.count);
  }

  	// in parent component
	//(change)="countChange($event)"> 

}
// just use it normal
@Output() itch:EventEmitter<any> = new EventEmitter();

//and call in html
<div appCollar (itch)='scratch()' >
Source

Also in JavaScript: